The Coastal Astelia
Strappy silvery green foliage and with the ability to grow in light shade, Astelia banksii is frost tolerant and evergreen.
It requires a well drained soil and it will grow in coastal conditions. In summer it will flower, small white flowers followed by pinkish red fruits.
Excellent for adding texture to the garden with the advantage of it being lower growing that the taller A. chathamica.
Suited to planting in clumps beneath trees or even growing in containers on a deck or outdoor living area.
How To Grow Astelia banksii – Comprehensive Growers Guide
Climate:
Astelia banksii thrives in temperate to subtropical climates. It is well-adapted to regions with moderate temperatures and can handle a range of conditions from coastal areas to more inland sites.
It prefers environments where there is a balance between warmth and moisture but is also relatively tolerant of cooler conditions. Suited to cool temperate to warm temperate zones, into sub tropical areas. Suitable for USDA Hardiness Zones 9 to 11. In areas with harsh winters, it may benefit from some protection, particularly if temperatures drop below freezing.
Soil:
This is not a plant that is particularly fussy about soil type as long as it is free draining.
A slightly acidic to neutral pH is best, ideally ranging from 5.5 to 7.0. While it can tolerate a variety of soil textures, it flourishes in sandy loam or loamy soils that allow for good drainage and air circulation around the roots.
Heavy clay soils should be avoided or amended with organic matter to improve drainage and reduce the risk of root rot.
Watering:
Astelia banksii requires consistent moisture to thrive, but it does not like to sit in waterlogged conditions.
Regular watering is essential, particularly during dry periods, but care should be taken not to overwater.
The plant benefits from deep watering that allows the soil to dry slightly between sessions.
In very hot climates or during prolonged dry spells, more frequent watering may be necessary, but always ensure that the soil remains well-drained.
Temperature Range:
Astelia banksii is tolerant of a range of temperatures but does best in mild conditions. It can handle temperatures as low as 10°F (-12°C) but may require some protection in areas where temperatures frequently drop below freezing.
Conversely, it can also handle warmer temperatures up to 85°F (30°C) provided it has adequate water and shade during the hottest part of the day.
In regions with extreme temperatures, it may need to be grown in a sheltered spot or provided with additional care to protect it from temperature extremes.
Fertiliser:
To promote healthy growth and lush foliage, Astelia banksii benefits from regular feeding. A balanced, slow-release fertiliser applied in early spring and mid-summer will support its growth.
Use a general-purpose fertiliser with an equal ratio of nitrogen, phosphorus, and potassium (such as 10-10-10) or a specific fertiliser formulated for ornamental grasses and perennials.
Avoid excessive fertilisation, which can lead to excessive leaf growth at the expense of overall plant health.
Organic options such as compost or well-rotted manure can also be beneficial, enhancing soil structure and providing slow-release nutrients.
How to Plant Astelia Banksii :
When planting Astelia banksii, choose a location that provides adequate sunlight and meets the plant’s soil and drainage requirements.
- Start by preparing the soil, ensuring it is well-drained and enriched with organic matter if necessary.
- Dig a hole twice the diameter of the root ball of the plant. This loosens the soil around the plant and assists with root development.
- Place the plant so that the top of the root ball is level with the surrounding soil surface. Backfill the hole with soil, firming it gently to eliminate air pockets.
- Water in thoroughly after planting to help settle the soil around the roots.
- Mulch around the base of the plant can help retain moisture and suppress weeds, keeping the mulch away from the stem to prevent rot.
Maintenance and Ongoing Care:
Astelia banksii is relatively low-maintenance but benefits from regular care to keep it looking its best.
- Remove any dead or damaged leaves to maintain the plant’s appearance and prevent disease.
- Weeding is important to prevent root competition and maintain looks.
- In colder climates, provide winter protection if necessary. In very cold climates subject to heavy frosts and freezes grow this plant in containers or cover the plant with a frost blanket.
Garden Uses:
Astelia banksii is a versatile plant that can be used in various garden settings.
Its bold foliage makes it an excellent choice for tropical, subtropical or temperate gardens, it provides good texture and color contrast.
It can be used as a focal point in garden beds, in mixed borders, or as part of a low-maintenance landscape design.
Due to its clumping nature, it is also ideal for use as a ground cover or for mass planting to create a lush, green carpet effect.
Astelia banksii is also well suited for use in coastal gardens due to its tolerance of salt spray and sandy soils.
It works well in container gardening, grow it in large pots in a courtyard or on a patio where its architectural form can be appreciated up close.
Its ability to grow dappled shade or partially shaded areas makes it a versatile plant providing a different texture and overall look to other shade-loving plants.
Overall, Astelia banksii is a durable and attractive plant that can be used in variety of garden styles, from modern minimalist to lush, tropical landscapes. With its ease of care and versatile uses, it is a valuable addition to a range of garden designs.
Summary Details
- Botanical Name: Astelia banksii
- Common Names: Shining Astelia, Silver Astelia
- Origin: New Zealand
- Family: Asteliaceae
- Genus: Astelia
- Cultivar Name: (Varies, but commonly grown varieties include ‘Red Elf’)
- Plant Type: Evergreen perennial
- Exposure/ Light: Partial shade to full sun
- Soil Type: Well-drained, loamy to sandy soil
- Soil Moisture: Moist, but well-drained
- pH Level: Acidic to neutral
- Climate Zone: USDA Zones 8-10
- Drainage: Excellent
- Water Requirements: Regular watering; avoid waterlogging
- Height: 1 to 1.5 meters (3 to 5 feet)
- Width: 1 meter (3 feet)
- Growth Habit: Clump-forming, rosette-like
- Lifespan: Long-lived perennial
- Landscaping Uses: Borders, groundcover, container planting, tropical and coastal gardens
- Garden Styles: Coastal, tropical, modern, and low-maintenance gardens
- Special Uses: Erosion control, accent plant in garden beds
- Plant Environment: Prefers sheltered, semi-shaded positions; can tolerate full sun in cooler climates
- Flowering Time :Spring
- Flowers : Small green but insignificant.
- Other Seasonal Interest: Attractive silver foliage provides year-round interest
- Special Uses: (Repeated, see above for landscaping and accent uses)
- Frost Tolerance: Moderate; can tolerate light frosts but may need protection in colder areas
- Drought Tolerance: Moderate; prefers consistent moisture but can tolerate short periods of drought
- Attracts Wildlife: Birds (especially in cooler climates)